Use EGL_LINUX_DMA_BUF_EXT to create GBM bo EGLImages

Xwayland was passing GBM bos directly to
eglCreateImageKHR using the EGL_NATIVE_PIXMAP_KHR
target. Given the EGL GBM platform spec claims it
is invalid to create a EGLSurface from a native
pixmap on the GBM platform, implying there is no
mapping between GBM objects and EGL's concept of
native pixmaps, this seems a bit questionable.

This change modifies the bo import function to
extract all the required data from the bo and then
imports it as a dma-buf instead when the dma-buf +
modifiers path is available.
5 jobs for xwayland_dma_buf in 7 minutes and 20 seconds (queued for 4 seconds)
Status Name Job ID Coverage
  Docker Image
passed debian-buster #13674149

00:00:24

 
  Build And Test
passed autotools #13674150

00:06:55

passed meson #13674151

00:03:12

passed meson-noglamor #13674152

00:02:36

passed mingw-cross-build #13674153

00:00:58